Process of making glue substitutes.



106. COMPOSITIONS,

COATING R PLASTIC.

Referencesz- Pick (German) 60,

(e? Adhesives). Grossnietsch.

UNITED STATES PATENT oFEroE.

Specification of Letters Patent.

Patented Feb. 26, 1907.

Application filed September 10,1906. Serial No. 334.034.

To all whom it may concern.-

Be it known that I, ALEXANDER BERN- STEIN, chemist, a subject of the German Emperor, residing at Berlin, Germany, Magdeburgerstrasse 9, have invented certain new and useful Improvements in Processes of Making Glue Substitutes; and I do hereby declare the following'to be a full, clear, and exact description or the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

' 'lnis invention relates to chemical combinations of casein which have the binding power of glue and may be used in all such cases in which ordinary glue has been applied. For this purpose the casein which may be in a wet or dry state, is mixed with water and a certain amount of an alkali or an alEalme salt is added, so as to dissolve the casein in a well-known manner. Thereafter the chlorid of a metal of the alkaline earths or te magnesium group is a e or example, chlorid of calcium barium, or ma nesium. It the same time an addition 0 a z 5 soluble silicate is made, such as silicate of sodium or otassium. I L lEe chlorids mentloned before-f01/a,l.=

ample, chlorid of magnesiumhave a dc composing effect on the soluble silicates, such as silicate of sodium. In this special case the chlorin will combine with the sodium, forming common salt, and a silicate of ma nesium is produced. This lattersub- EfamTn sduble in water, and ii no casein were present the silicate of magnesia would be precipitated in solid pieces. However, the presence of the dissolved casein, which is a glutinous-substance, has the effect of preventing this precipitation, and the silicate of magnesia remains suspended in a slimy state, thereby adding to the binding power of the product.

The process may be carried out in the following manner: To four hundred cubic centimeters of water one hundred grams of dry casein are a e and brought into solution 1n a well-known manner by the addition of twelve grams of soda. A solution is made containing ten grams of crystalline ma nesium chlorid in ninety cubic centimeters o 156, Ausgegeben Nov. 18, 1891. Wittkowsky, 537,096, April 9, 1895 (English). (German) 152.895. Aus esreben. Julv 5 I902 (an)- water, and this is added to the casein solution under constant stirring and keeping the temperature of the mixture at about 40 centigrade. Upon the addition of sixty cubic centimeters of the ordinary commercial sili- 5 5'";

cate of sodium the decomposition of theIsTt er W1 ta e pace, as described above, and a compound of great binding power is formed.

The silicate can be added before the chlorid, or both may be added together to the casein solution.

If the finished product is deprived of water, the dry casein-glue will swell in cold wa- 21 and dissolve in warm water in t e same way as ordinary glue.

All such additions as are now made to ordinarv lue for various technical purpo 's' may be made in the same manner to the new product here described.

I am aware that a mixture of casein with water-glass and lime has been used. In my process the decomposition of water-glass is ehected by a salt of a metal-for example, magnesium chlorid in solution-and a mixture of the alkaline solution of casein with -the decomposed water-glass forms a glue substitute which is stable in its physical condition, while the mixtures of casein with water-glass and lime must be used in a fresh state, as they soon begin to harden.

What I claim as my invention, and desire to secure by Letters Patent, is-

1. The process of making a substitute for glue, which consists in making an alkaline solution of casein, adding thereto a s.o lntion efcmerrmof magnesium, and finall adding "meters silicate oij sgdm'substantial y as described.

' 2. The James of making a substitute for glue, whic consists in dissolving dry casein in a solution containing soda dissolved in water, adding thereto a solution of chlorid of magnesium, and adding to the mixture sodium silicate, substantially as described.

In testimony whereof I afiix my signature in presence of two witnesses.

ALEXANDER BERNSTEIN. Witnesses:

WALTER SCHILL, WILHELM DORME. 

